William i



(ModeL) W. I. BUNKER. 3001mm GHAIR SPRING.

\ WITNESSES INVENT'OR 6M6 g BY WWI/1:7 v m N. PETEZRS. Phmn-Lilhographen Wnhingwn. v.0

UNITE STATES PATENT OFFICE.

\(VILLIAM I. BUNKER, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE ROCKER SPRING COMPANY, OF SAME PLACE.

' ROCKING-CHAIR SPRING.

SPECIFICATION forming part of Letters Patent No. 354,039, dated December 7, 1886.

Application filed April 9,1884. Serial No. 127,152. (Motleh) To all whom it may concern:

Be it known that I, \VILLIAM I. BUNKER, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in RockingCh-air Springs, of which the following is a specification.

My object is to make a spring for platform rocking-chairs which is simple in construction, easy of application, and of such form that it will effectively keep the rockers in line with the base-rails. The most desirable form of rocking-chair spring is that form in which the greatest breadth of spring in proportion to its length is secured, and these proportions must be consistent with sufficient rigidity of the spring to preventtoo great separation of the parts of the chair;

My present invention consists in constructing a spring for rocking-chairs of a heavy wire bent into a broad bow or loop having its ends secured to the rocker and base, respectively, by suitable fastening devices, as hereinafter particularly described and claimed.

In the accompanying drawings, Figure 1 shows the preferred form of spring, and Fig. 2 shows a modification thereof. 'Fig 3 shows staples as thefastening devices, and Fig. althe ends of the spring flattened and provided with screwholes.

I prefer to construct the spring of a heavy wire bent into a broad bow, A. The ends of the bow may be made to cross each other, as shown in Fig. 1, or they may be brought together when made. As shown in the drawings, the ends of the bow are secured within sockets B B upon the rocker and base-rail, respectively. \Vhen fastening the springs upon the respective sides of the chair, care should be taken to place them in reverse order, so that they will work against each other, thus neutralizing the tendency of each to throw the rockers out ofline with the base. The fastening devices may be provided with sockets, as shown in Figs. 1 and 2; or they may consist of simple staples, as shown in Fig. 3; or the ends of the bow may be flattened and provided with screw holes, as shown in Fig. 4. In the first form the spring is secured and held in place by having its ends inserted in the sockets, respectively; in the second the staples serve to hold it in place, and in the third common wood-screws inserted in the holes in the flattened ends may be used. I prefer, however, to use the sockets,and to have them so constructed as to give a considerable bearing for the ends of the wire forming the spring.

Some of the advantages of my present form of spring are its cheapness and simplicity, and its capability of being used interchangeably either as a right or left hand spring, thus rendering special construction into rights and lefts unnecessary, even when such springs are desired.

I am aware of Patents Nos. 202,291 and 242,442, which show flat springs in the form of vertical loops or bows, and 1 do not claim this construction.

I claim 1. The combination, with each of the rockers an d base-rails of a platform rocking-chair, of a heavy bowspring comprising a single horizontal spiral coil rigidly secured at its ends to said parts, respectively, one end to the rocker and the other to the base-rail, and forming the connection between the seat and base parts of the chair, substantially as described.

2. The combination, with each of the rockers and base-rails ot a platform rocking-chair, of a heavy bow-spring comprising a single horizontal spiral coil, and fastening devices having sockets for securing the same to the rocker and base-rail at its ends, the springs being rigidly secured by such fastening devices to the rocker and base-rail, one end to each, and forming the connection between the seat and base parts of the chair, substantially as described.

\VILLIAM I. BUNKER.

Witnesses:

CHARLES C. LINTHIcUM, DOUGLAS DYRENFORTH. 

